Blading construction for turbo-compressor impellers.



O. BANNER. BLAOING CONSTRUCTION FOR TURBO COMPRESSOR IMPELLERS.

APPLICATION FILED SEPT-23.1912.

Patented Reb. 27,1917.

OTTO BANNER, OF EASTON, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND COMPANY, 0F NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

BLADING CONSTRUCTION FOR 'ILURBO-COlllIlERlElSSOR4 IMPELLERS.

specificati ers Patent. Patemtd Feld?. 27, 191K?.

Application filed September 23, 1912. Serial No. 721,937.

To all whom t may concern.'

Be it known that I, OTTO BANNER, a subject of the German Emperor, residing at Easton, in the countyof Northampton and .State of Pennsylvania, have invented a certain new and useful Improvement in Blading Construction for Turbo-Compressor Impel- 1ers, of which the following is a specification.

This invention relates to impellers for turbo compressors and more particularly to that type of impeller in which the blades are formed of sheet material, the edges of which are bent and hammered into flanges perpendicular to the blade portion the flanges belng riveted to the disk and cover of the impeller.

' In practice it has been found that the ends of these blades give way near their ed es under the high centrifugal strain to which their lcenters are subjected and semicircular pieces are removed bodily from the ends of the blades impairing the efliciency of the impeller. blade of the thickness and weight necessary to bear the stress on the outer end and the' manufacturing cost of making the outer ends of such blades integrally thicker is prohibitive.

The object of the present invention is to provide a way of strengthening the outer ends of such blades so that thin sheet material can be used for forming the larger portion of the blade.

This invention consists essentially in reinforcing pieces secured at the outer end of the blades. These reinforcing pieces may be either of sheet material such as used for the blades or may be of tougher and stronger material incapable of bending, which has to be milled to proper form. Practical embodiments of this idea are shown in the accompanying drawings in which:

Figure 1 shows a portion of an impeller with one 'form of my blade shown therewith,

Fig. 3, a similar section of a modified form of blading.

In Fig. 1 the impeller is shown as consist- It is undesirable to make the Whole- Fig. 2 shows a section taken on the line II-II of Fig. 1, and

ing of a disk l, a cover 2 and blades 3. The blades are of sheet material with bent flanges 4 and 5, both extending in the same direction from the blade and secured to the disk and cover by rivets G. The reinforcing piece 7 consists of a short piece of similar sheet material, thinner in its middle portion, with flanges 8 and 9 extending oppositely from the flanges of the blade and secured to the disk and cover by rivets l0, the body portions of the blade and reinforcing piece being secured together by rivets 1l.

In the modification shown in Fig. 3' the impeller blade is constructed with a reinforcing piece similar to that illustrated in Figs. l and 2, but with the provision of an additional reinforcing piece l2 on the opposite side of the impeller blade, this reinforcing piece 12 consisting of a plate thinner at lts center and having flanges extending in the same direction as the flanges 4 and 5 of the blade, so that it rests inside the blade flanges .and is secured to the disk and cover by the same rivets that secure the impeller .blade thereto, the 'body portions of the impeller blade and reinforcing pieces being riveted together.

It is to be understood that the present showing and description discloses only certain specified modifications of my invention, and other forms and modifications are included within the spirit and scope of the invention as expressed in the appended claim.

What I claim is:

An impeller for turbo compressors comprising a disk, a cover, blades having flanges riveted to said disk and cover, and reinforcing pieces extending' across only the outer ends of said blades, said reinforcing pieces being riveted to said bladesand having2k flanges riveted to said disk and cover and having their central -portions thinner than their edges. l

In testimony whereof,'I have hereunto set my hand.

OTTO BANNER. Witnesses:

F. A. POPE, PAUL HOFFMAN. 

